qnet.convert.to_qutip module

Conversion of QNET expressions to qutip objects.

Summary

Functions:

SLH_to_qutip Generate and return QuTiP representation matrices for the Hamiltonian and the collapse operators.
convert_to_qutip Convert a QNET expression to a qutip object

__all__: SLH_to_qutip, convert_to_qutip

Reference

qnet.convert.to_qutip.convert_to_qutip(expr, full_space=None, mapping=None)[source]

Convert a QNET expression to a qutip object

Parameters:
  • expr – a QNET expression
  • full_space (HilbertSpace) – The Hilbert space in which expr is defined. If not given, expr.space is used. The Hilbert space must have a well-defined basis.
  • mapping (dict) – A mapping of any (sub-)expression to either a quip.Qobj directly, or to a callable that will convert the expression into a qutip.Qobj. Useful for e.g. supplying objects for symbols
Raises:

ValueError – if expr is not in full_space, or if expr cannot be converted.
qnet.convert.to_qutip.SLH_to_qutip(slh, full_space=None, time_symbol=None, convert_as='pyfunc')[source]

Generate and return QuTiP representation matrices for the Hamiltonian and the collapse operators. Any inhomogeneities in the Lindblad operators (resulting from coherent drives) will be moved into the Hamiltonian, cf. move_drive_to_H().

Parameters:
  • slh (SLH) – The SLH object from which to generate the qutip data
  • full_space (HilbertSpace or None) – The Hilbert space in which to represent the operators. If None, the space of shl will be used
  • time_symbol (sympy.Symbol or None) – The symbol (if any) expressing time dependence (usually ‘t’)
  • convert_as (str) – How to express time dependencies to qutip. Must be ‘pyfunc’ or ‘str’
Returns:

tuple (H, [L1, L2, ...]) as numerical qutip.Qobj representations, where H and each L may be a nested list to express time dependence, e.g. H = [H0, [H1, eps_t]], where H0 and H1 are of type qutip.Qobj, and eps_t is either a string (convert_as='str') or a function (convert_as='pyfunc')
Raises:

AlgebraError – If the Hilbert space (slh.space or full_space) is invalid for numerical conversion